Motor-control system.



E. w. STULL. MOTOR CONTROL SYSTEM.

APPLIUATION FILED AUG. 27, 1906.

Patented N0ir.3,19'08.

2 sums-SHEET 1.

E. W. STULL.

MOTOR, CONTROL SYSTEM. APPLICATION FILED AUG. 27, 1906.

Patented Nov. 3, 1908.

2 SHEETS-SHEET 2.

' lowing UNITED STATESETENT ensues. v

I'JlNlh/IE'JJ'I W. STULL, OF NORWOOD, OHIO, ASSIGNOR TO ALLIS-OHALMERS COMPANY, A GOR- PORATION OF NEW JERSEY, AND THE BULLOCK ELECTRIC MANUFACTURING COMPANY,

A CORPORATION OF OHIO.

MOTOR-CONTROL SYSTEM.

of Ohio, have invented certain'new and use.

ful Improvements in'Motor-Oontrol Systems,

of which the following is a full, clear, and exact specification.

My invention relates to electric controllers and especially to series-parallel controllers for motors having commutating, oles.

It is found that by the use 0 additional poles placed midway between the main poles commutation is greatly assisted and motors can be worked at a muchlower field stre than would otherwise be possible. Such eing the case, it is the object of my present invention to provide a controller which not only controls the motors by connecting them in series and parallel relation and by cutting in and out a series resistance, but also regulates them by weakening their fields, thus ala strong torque at starting and a higher running speed.

To this end my'invention consists inone aspect of the combination of a plurality of motors having commutating poles and a controller for. connecting them in series and parallel relation.

In another aspect my invention consists of a lilurality' of motors and resistances, toget er with a controller arranged to connect said motors in series and parallel and to connect said resistances in series with the motors or in shunt to the motor field windings.

Other features of my invention will appear from the s ecification and drawings and will be particu arly set forth in the claims.

Figure 1 is a diagram showing a develop ment of a two-motor controller embodying my invention. Fig. 2 is a set of simple diagrams showing the connections of the motors and resistances for the different positions of the controller of Fig. 1. Fig. 3 is a diagram showing a development of a four-motor controller embodying my invention; and Fig. 4

' is a set of simple diagrams showing the connections of the motors and the resistances inthe'most important positions of the (3011-. troller of Fig. 3. The'diagrams of Figs. 2 and 4 are numberedto agree with the corre sponding operative positions of the controller. and 2, A and B are-the motors to be contr lled., These mo Referring first to Figs.

Specification of Letters Patent.

Patented Nov. 3, 1908.

Application filed August 27, 1906. Serial No. 332,13.

In addition to the main These commutatin-g poles,.as they are now generally called, serve to assist commutation 111a manner so well understood that it is not deemed necessary to explain it here. In

Figs. 1 and 3, the armatures of the motors are shown connected between the windin s of the commutating poles, but manifesty both commutating windings may be on the same electrical side of the motor, as shown in Figs. 2 and 4.

The motors A and B are regulated by a series-parallel controller, the drum 0 of which,

as shown in the development'of Fig. 1, haslG operative positions. The first seven of these positions are series positions, while positions 8, 9 and 10 are parallel positions. The reversing switch and its connections are omitted -from the diagram in order to add to the simplicity of the latter. .A and B, there are resistances 15, 16 and 17 Besides the two motors under the control of the controller. Each of these resistances may be composed of a lurality of units and in the drawing eac 1 is shown with two units, though obviously any number may be used. The resistance 15 is ar-. ranged to be connected in series with thetwo motors for starting purposes, and to be cut out a unit at a time, as indicated in diagrams #1, #2 and #3 of Fig. 2. The resistances atand 17 are also connected in series with the motors for starting purposes and are cut out simultaneously a unit at a time, as shown in diagrams #3, #4 and #5 of Fi 2. when the controller is move into position 6,

the resistances 16 and17are connected in and servi to increase the motor speed bothby g the motor field strength and by. the resistance of the motor Moreover,95

circuit. Because of the comrnutating poles this field weakening can be safely done without causing sparking at the brushes.

When the controller is'moved to position 8, the motor connections are changed from series to parallel and the resistances 16 and 17 are disconnected. At this first parallel position in this modification the motors have no external resistance in circuit with them. In position 9 the resistances 16 and 17 are again connected in shunt respectively to the field windings of the motors A and B,-while in position 10 this shunt resistance is diminished to still further increase the motor speed. I

In the arrangement shown in Figs. 3 and 4 instead of the single motors A and B there are airs of motors A and A, and B and B Eaoi individual motor has main and com mutating poles as in Fig. 1. The two motors of a pair are controlled as a unit, and the two pairs are connected in series and in parallel positions by thedrum C in much the same manner as the two single motors were in the arrangement of Fig. 1. As in the controller in Fig. 1 there are the resistances 15, 16 and 17, but there are two additional controller contacts. These two extra contacts are for the extra connections which must lead from the controller to the twoadditional motors, for notonly is each terminal of each motor connected to a controller contact but a point intermediate between the armature and main field windings is likewise so connected so that the field windings may be shunted by the proper resistances. These latter connections should be separate for each motor, so that there shall be no internal interconnection between the two motors of a pair. For this reason when a group of motors is used instead of a single motor, each additional motor necessitates an additional controller contact.

As in the arrangement oiv Fig. 1 the controller'drum C of Fig. 3 has 10 operative positions, 1 to 7 being series positions and 8 v to 10 parallel positions. Although the arrangement of controller segments in Fig. 3 is difierent from that in Fig. yet between positions 1 to 7 the controller connects the motors and resistances in. ractically the same manner as in Fig. 1. herefore some of the less important connection diagrams are omitted in Fig. 4. In position 8, however, the controller of Fig. 3 again connects in resistance 15 in series, while the two airs of motors are connected in parallel. ion the controller is moved to positions 9 and 10, the halves of the resistance 15ers successively cutout of circuit. When a pair of motors is in'the unit of control as in Big. 3, instead. of a single motor as in Fig. 1, it is oftentimes disadvantageous, even with commutating poles to prevent sparking at the commutators, to attempt to shunt the field windings eoaee 1 in the full on position of the controller,

taken by the two motors of a pair to be greatly and progressivelymagnified, resulting in an overload on onemotor of a pair and a low efiiciency in the other motor. For this reason the main field windings of the motors are not shunted in theparallel positions in Figs. 3 and 4; instead the resistance 15 is reinserted in circuit and then gradually out out. I

Obviously instead of a pair of motors, a group of any number of motors could be used.

Many changes in the particular arrangements here shown and described will readily occur to any one skilled in the art and inthe following claims Iaim to cover all modifications which come within the spirit and scope of m invention.

W at I claim as new and desire to secure by Letters Patent is 1. In combination, a motor having commutating poles, a controller therefor, and a plurality of resistances, one of said resistances being arranged so that it can only be out out or connected in series with the motor, while another resistance is arranged to be connected either in serieswith the motor, or in shunt to the motor. fieldwindings.

2. In combination, a motor having antisparking windings, a controller, and a plurality of sets of resistances,"one of said sets being arranged so that it can only be cut out or connected in vseries with the motor,

whileanother set is arranged to be connected either in series with the motor, in shunt to the motor field windings, or .tkg be cut out.

3. In combination, a motor having commutating poles, a controller, and a. plurality of sets of resistances, one of said sets being arranged so thatit can'only be out out or connected in series with the motor, while an aiices and can cut out said resistances gradually, and can also connect certain of said resistances in shunt to the motor main field windings.

5. In combination, a plurality of motors having anti-sparking windings, a. controller therefor, a plurality of resistances, and con neetions whereby said controller can connect said motors in series with all of said resistances, and can graduallly cutout one of said resistances separately and others of said re- 1 sistances simultaneously.

IPI'OVidGCl with commutating poles, at con- 8. In combination, aplurality of motors troller therefor, a plurality of resistances, and connections whereby said controller can connect the motors in series and in arallel with each other and in series with aii ofsaid re.-

sistances, ,can' cut out .said resistances, and

can shuntthe motor main field Windingsby' certain of said resistances.

9.. In combination, a plurality of motors provided with commutating'windings, a plurality of resistances, and a controller arranged to connect said motors in series and in parallel, and said resistances in series with the motors or in shunt to the motor field windmg i 10. In combination, a motor, a controller therefor, and a plurality of resistances, one of said resistances'being arranged sothatjit arranged to be connected either in series with the motor, or in shunt tothe motor field Windin s. i 4

11. n-combination, a motor, a controller therefor, and a plurality of sets of resistances,

one of said sets being'arranged so that it can onlyybe cut out or connected in series with the motor, while another of said sets is arranged to be connectedeither in series with the -motor or in shunt to the motor field windin s.=

12. a combination, a motor, a controller, and a plurality of sets of resistances, one of said sets being arranged so that it can only be cut out or connected in series with the motor, while another of said sets is arranged to be connected'in whole'or in part in series with the -r nlotor or in shunt to the motorfield win s '60 i "131 n coinbination, a plurality of motors, "a ccntrollertherefor, a pluralityiof resists ances, and connections whereby the controller can connect said motors in series with all of said resistances and can cut out said resistances gradually, and can also connect certain of said resistances in shunt to the motor field windings.

14. In combination, a plurality of motors,

a controller therefor, a plurality of resistances, and connections whereby the controller can connect said motors 1n serles with all of saldresistances, andv can connect certain of said resistances in shunt tothe motor field windings. 15. In combination, a motor, a controller therefor, and a plurality of resistances in series, one of which resistances is arranged to be gradually out out separately and others of which are arranged to be gradually cut out simultaneously.

' 16. In combination, aplurality of motors, a controller therefor, a plurality of resist-- ances, and connections whereby said controller can connect said motors in series with all of said resistances and can cut out one of said resistances separatel andiothersof said resistances simultaneous y.

' 17. In combination, a plurality of motors, a controller therefor, a plurality of resistances, and connections whereby said controller can connect the motors in series and in parallel with each other and in series with all of said resistances and can shunt the motor field windings by certain of the resistances.

18. Incombination, a plurality of motors and resistances, and a controller arranged to 'connectsaid motors inseries and in parallel and said resistances in series with the motors .0 1"-ifl shunt with the motor field windings.

can only be cut out or connected in series with the motor, while'another resistance'is 19; in combination, a pluralitymf motors,

.a' series-parallel controller therefor, a luralsistances in series with said motors, and-centainof said reslstances in shunt to the'motor field windings when the motors areeither 1n series or in parallel.

20. In combination, aplu'rality-of motors, a series-parallel controller therefor, a lurality of resistances, and connections w ereby the controller can connect certain of said resistances in series with said motors and can connect certain-of said resistances in shunt to the motor field windings when the motors are connected in arallel. k In testimony w ereof affiX-my signature, in the presence of two witnesses.

EMMETT W. s'rUnL.

Witnesses RUBELLA RonmsoN, FRED J. Kmsnr. 

